Tryptophan Metabolites, Pyridoxine (Vitamin B(6)) and Their Influence on the Recurrence Rate of Superficial Bladder Cancer

This double-blind randomised phase III trial was designed to assess the effect of pyridoxine administration on the recurrence of Ta and Tl transitional cell tumours of the bladder. The trial accrued 291 patients and showed no significant difference between the pyridoxine and placebo treatment groups with respect to the time to first recurrence or the recurrence rate. Adjustment for the main prognostic factors, namely the recurrence rate prior to entry, the number of tumours at entry, the G grade and the levels of the tryptophan metabolites kynurenine plus acetyl kynurenine at entry do not change the overall conclusions.